diff options
Diffstat (limited to 'drivers/usb/storage/transport.c')
| -rw-r--r-- | drivers/usb/storage/transport.c | 46 |
1 files changed, 38 insertions, 8 deletions
diff --git a/drivers/usb/storage/transport.c b/drivers/usb/storage/transport.c index e20dc525d17..589f6b4404f 100644 --- a/drivers/usb/storage/transport.c +++ b/drivers/usb/storage/transport.c @@ -696,7 +696,7 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us) /* device supports and needs bigger sense buffer */ if (us->fflags & US_FL_SANE_SENSE) sense_size = ~0; - +Retry_Sense: US_DEBUGP("Issuing auto-REQUEST_SENSE\n"); scsi_eh_prep_cmnd(srb, &ses, NULL, 0, sense_size); @@ -720,6 +720,21 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us) srb->result = DID_ABORT << 16; goto Handle_Errors; } + + /* Some devices claim to support larger sense but fail when + * trying to request it. When a transport failure happens + * using US_FS_SANE_SENSE, we always retry with a standard + * (small) sense request. This fixes some USB GSM modems + */ + if (temp_result == USB_STOR_TRANSPORT_FAILED && + (us->fflags & US_FL_SANE_SENSE) && + sense_size != US_SENSE_SIZE) { + US_DEBUGP("-- auto-sense failure, retry small sense\n"); + sense_size = US_SENSE_SIZE; + goto Retry_Sense; + } + + /* Other failures */ if (temp_result != USB_STOR_TRANSPORT_GOOD) { US_DEBUGP("-- auto-sense failure\n"); @@ -768,17 +783,32 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us) /* set the result so the higher layers expect this data */ srb->result = SAM_STAT_CHECK_CONDITION; - /* If things are really okay, then let's show that. Zero - * out the sense buffer so the higher layers won't realize - * we did an unsolicited auto-sense. */ - if (result == USB_STOR_TRANSPORT_GOOD && - /* Filemark 0, ignore EOM, ILI 0, no sense */ + /* We often get empty sense data. This could indicate that + * everything worked or that there was an unspecified + * problem. We have to decide which. + */ + if ( /* Filemark 0, ignore EOM, ILI 0, no sense */ (srb->sense_buffer[2] & 0xaf) == 0 && /* No ASC or ASCQ */ srb->sense_buffer[12] == 0 && srb->sense_buffer[13] == 0) { - srb->result = SAM_STAT_GOOD; - srb->sense_buffer[0] = 0x0; + + /* If things are really okay, then let's show that. + * Zero out the sense buffer so the higher layers + * won't realize we did an unsolicited auto-sense. + */ + if (result == USB_STOR_TRANSPORT_GOOD) { + srb->result = SAM_STAT_GOOD; + srb->sense_buffer[0] = 0x0; + + /* If there was a problem, report an unspecified + * hardware error to prevent the higher layers from + * entering an infinite retry loop. + */ + } else { + srb->result = DID_ERROR << 16; + srb->sense_buffer[2] = HARDWARE_ERROR; + } } } |